Skip equation code that doesn't compile instead of failing the preset

src/libprojectM/MilkdropPreset/CustomShape.hpp

@@ -35,7 +35,7 @@ class CustomShape
 
     /**
      * @brief Compiles all code blocks and runs the init expression.
-     * @throws MilkdropCompileException Thrown if one of the code blocks couldn't be compiled.
+     * If one of the code blocks can't be compiled, a warning is logged and the code is skipped, like in Milkdrop.
      */
     void CompileCodeAndRunInitExpressions();
 

src/libprojectM/MilkdropPreset/CustomWaveform.hpp

@@ -33,7 +33,7 @@ class CustomWaveform
 
     /**
      * @brief Compiles all code blocks and runs the init expression.
-     * @throws MilkdropCompileException Thrown if one of the code blocks couldn't be compiled.
+     * If one of the code blocks can't be compiled, a warning is logged and the code is skipped, like in Milkdrop.
      * @param presetPerFrameContext The per-frame context to retrieve the init Q vars from.
      */
     void CompileCodeAndRunInitExpressions(const PerFrameContext& presetPerFrameContext);

src/libprojectM/MilkdropPreset/PerFrameContext.cpp

@@ -139,7 +139,14 @@ void PerFrameContext::EvaluateInitCode(PresetState& state)
             error = "[PerFrameContext] Could not compile per-frame init code.";
         }
         LOG_DEBUG("[PerFrameContext] Failed per-frame INIT code:\n" + state.perFrameInitCode);
-        throw MilkdropCompileException(error);
+        // Like Milkdrop, only this code block is disabled, the preset is still used.
+        LOG_WARN(error);
+        for (int q = 0; q < QVarCount; q++)
+        {
+            q_values_after_init_code[q] = 0;
+            state.frameQVariables[q] = 0;
+        }
+        return;
     }
 
     projectm_eval_code_execute(initCode);
@@ -260,7 +267,9 @@ void PerFrameContext::CompilePerFrameCode(const std::string& perFrameCode)
             error = "[PerFrameContext] Could not compile per-frame code.";
         }
         LOG_DEBUG("[PerFrameContext] Failed per-frame code:\n" + perFrameCode);
-        throw MilkdropCompileException(error);
+        // Like Milkdrop, only this code block is disabled, the preset is still used.
+        LOG_WARN(error);
+        return;
     }
 }
 

src/libprojectM/MilkdropPreset/PerFrameContext.hpp

@@ -46,14 +46,14 @@ class PerFrameContext
 
     /**
      * @brief Compiles and runs the preset init code.
-     * @throws MilkdropCompileException Thrown if the per-frame init code couldn't be compiled.
+     * If the per-frame init code can't be compiled, a warning is logged and the code is skipped, like in Milkdrop.
      * @param perFrameInitCode The init code.
      */
     void EvaluateInitCode(PresetState& state);
 
     /**
      * @brief Compiles the per-frame code and stores the code handle in the class.
-     * @throws MilkdropCompileException Thrown if the per-frame code couldn't be compiled.
+     * If the per-frame code can't be compiled, a warning is logged and the code is skipped, like in Milkdrop.
      * @param perFrameCode The code to compile.
      */
     void CompilePerFrameCode(const std::string& perFrameCode);

src/libprojectM/MilkdropPreset/PerPixelContext.cpp

@@ -124,7 +124,9 @@ void PerPixelContext::CompilePerPixelCode(const std::string& perPixelCode)
             error = "[PerPixelContext] Could not compile per-pixel code.";
         }
         LOG_DEBUG("[PerPixelContext] Failed per-pixel code:\n" + perPixelCode);
-        throw MilkdropCompileException(error);
+        // Like Milkdrop, only this code block is disabled, the preset is still used.
+        LOG_WARN(error);
+        return;
     }
 }
 

src/libprojectM/MilkdropPreset/PerPixelContext.hpp

@@ -48,7 +48,7 @@ class PerPixelContext
 
     /**
      * @brief Compiles the per-pixel code and stores the code handle in the class.
-     * @throws MilkdropCompileException Thrown if the per-pixel code couldn't be compiled.
+     * If the per-pixel code can't be compiled, a warning is logged and the code is skipped, like in Milkdrop.
      * @param perPixelCode The code to compile.
      */
     void CompilePerPixelCode(const std::string& perPixelCode);

src/libprojectM/MilkdropPreset/ShapePerFrameContext.cpp

@@ -160,7 +160,13 @@ void ShapePerFrameContext::EvaluateInitCode(const std::string& perFrameInitCode,
             error = "[ShapePerFrameContext] Could not compile custom shape " + std::to_string(shape.m_index) + " per-frame init code.";
         }
         LOG_DEBUG("[ShapePerFrameContext] Failed custom shape per-frame INIT code:\n" + perFrameInitCode);
-        throw MilkdropCompileException(error);
+        // Like Milkdrop, only this code block is disabled, the preset is still used.
+        LOG_WARN(error);
+        for (auto* tVar : t_vars)
+        {
+            *tVar = 0;
+        }
+        return;
     }
 
     projectm_eval_code_execute(initCode);
@@ -195,7 +201,9 @@ void ShapePerFrameContext::CompilePerFrameCode(const std::string& perFrameCode,
             error = "[ShapePerFrameContext] Could not compile custom shape " + std::to_string(shape.m_index) + " per-frame code.";
         }
         LOG_DEBUG("[ShapePerFrameContext] Failed custom shape per-frame code:\n" + perFrameCode);
-        throw MilkdropCompileException(error);
+        // Like Milkdrop, only this code block is disabled, the preset is still used.
+        LOG_WARN(error);
+        return;
     }
 }
 

src/libprojectM/MilkdropPreset/ShapePerFrameContext.hpp

@@ -41,15 +41,15 @@ class ShapePerFrameContext
 
     /**
      * @brief Compiles and runs the preset init code.
-     * @throws MilkdropCompileException Thrown if one of the custom shape init code couldn't be compiled.
+     * If one of the custom shape init code can't be compiled, a warning is logged and the code is skipped, like in Milkdrop.
      * @param perFrameInitCode The init code.
      * @param shape The shape this context belongs to.
      */
     void EvaluateInitCode(const std::string& perFrameInitCode, const CustomShape& shape);
 
     /**
      * @brief Compiles the per-frame code and stores the code handle in the class.
-     * @throws MilkdropCompileException Thrown if one of the per-frame code couldn't be compiled.
+     * If one of the per-frame code can't be compiled, a warning is logged and the code is skipped, like in Milkdrop.
      * @param perFrameCode The code to compile.
      * @param shape The shape this context belongs to.
      */

src/libprojectM/MilkdropPreset/WaveformPerFrameContext.cpp

@@ -122,7 +122,13 @@ void WaveformPerFrameContext::EvaluateInitCode(const std::string& perFrameInitCo
             error = "[WaveformPerFrameContext] Could not compile custom wave " + std::to_string(waveform.m_index) + " per-frame init code.";
         }
         LOG_DEBUG("[WaveformPerFrameContext] Failed custom wave per-frame INIT code:\n" + perFrameInitCode);
-        throw MilkdropCompileException(error);
+        // Like Milkdrop, only this code block is disabled, the preset is still used.
+        LOG_WARN(error);
+        for (auto* tVar : t_vars)
+        {
+            *tVar = 0;
+        }
+        return;
     }
 
     projectm_eval_code_execute(initCode);
@@ -157,7 +163,9 @@ void WaveformPerFrameContext::CompilePerFrameCode(const std::string& perFrameCod
             error = "[WaveformPerFrameContext] Could not compile custom wave " + std::to_string(waveform.m_index) + " per-frame code.";
         }
         LOG_DEBUG("[WaveformPerFrameContext] Failed custom wave per-frame code:\n" + perFrameCode);
-        throw MilkdropCompileException(error);
+        // Like Milkdrop, only this code block is disabled, the preset is still used.
+        LOG_WARN(error);
+        return;
     }
 }
 

src/libprojectM/MilkdropPreset/WaveformPerFrameContext.hpp

@@ -35,15 +35,15 @@ class WaveformPerFrameContext
 
     /**
      * @brief Compiles and runs the preset init code.
-     * @throws MilkdropCompileException Thrown if the custom wave init code couldn't be compiled.
+     * If the custom wave init code can't be compiled, a warning is logged and the code is skipped, like in Milkdrop.
      * @param perFrameInitCode The init code.
      * @param waveform The waveform this context belongs to.
      */
     void EvaluateInitCode(const std::string& perFrameInitCode, CustomWaveform& waveform);
 
     /**
      * @brief Compiles the per-frame code and stores the code handle in the class.
-     * @throws MilkdropCompileException Thrown if the custom wave per-frame code couldn't be compiled.
+     * If the custom wave per-frame code can't be compiled, a warning is logged and the code is skipped, like in Milkdrop.
      * @param perFrameCode The code to compile.
      * @param waveform The waveform this context belongs to.
      */

src/libprojectM/MilkdropPreset/WaveformPerPointContext.cpp

@@ -110,7 +110,9 @@ void WaveformPerPointContext::CompilePerPointCode(const std::string& perPointCod
             error = "[WaveformPerPointContext] Could not compile custom wave " + std::to_string(waveform.m_index) + " per-point code.";
         }
         LOG_DEBUG("[WaveformPerPointContext] Failed custom wave " + std::to_string(waveform.m_index) + " per-point code:\n" + perPointCode);
-        throw MilkdropCompileException(error);
+        // Like Milkdrop, only this code block is disabled, the preset is still used.
+        LOG_WARN(error);
+        return;
     }
 }
 

tests/libprojectM/CMakeLists.txt

@@ -30,6 +30,7 @@ add_executable(projectM-unittest
         HLSLParserTest.cpp
         HLSLModuloTest.cpp
         LoggingTest.cpp
+        EquationCompileErrorTest.cpp
         MilkdropShaderCommentParsingTest.cpp
         PCMTest.cpp
         PresetFileParserTest.cpp
@@ -48,6 +49,7 @@ add_executable(projectM-unittest
 target_compile_definitions(projectM-unittest
         PRIVATE
         PROJECTM_TEST_DATA_DIR="${CMAKE_CURRENT_LIST_DIR}/data"
+        $<TARGET_PROPERTY:projectM::Eval,INTERFACE_COMPILE_DEFINITIONS>
         )
 
 # Test includes a header file from libprojectM with its full path in the source dir.
@@ -56,6 +58,8 @@ target_include_directories(projectM-unittest
         "${PROJECTM_SOURCE_DIR}/src/libprojectM"
         "${PROJECTM_SOURCE_DIR}"
         "${PROJECTM_SOURCE_DIR}/vendor/hlslparser/src"
+        # For tests using the expression contexts directly.
+        $<TARGET_PROPERTY:projectM::Eval,INTERFACE_INCLUDE_DIRECTORIES>
         )
 
 target_link_libraries(projectM-unittest

tests/libprojectM/EquationCompileErrorTest.cpp

@@ -0,0 +1,57 @@
+#include <gtest/gtest.h>
+
+#include <MilkdropPreset/PerFrameContext.hpp>
+
+#include <projectm-eval.h>
+
+using libprojectM::MilkdropPreset::PerFrameContext;
+
+namespace {
+
+/**
+ * PresetState needs an OpenGL context, so the expression context is set up with its own memory here.
+ */
+class EquationCompileErrorTest : public testing::Test
+{
+protected:
+    void SetUp() override
+    {
+        memory = projectm_eval_memory_buffer_create();
+        context = std::make_unique<PerFrameContext>(memory, &registers);
+        context->RegisterBuiltinVariables();
+    }
+
+    void TearDown() override
+    {
+        context.reset();
+        projectm_eval_memory_buffer_destroy(memory);
+    }
+
+    projectm_eval_mem_buffer memory{};
+    PRJM_EVAL_F registers[100]{};
+    std::unique_ptr<PerFrameContext> context;
+};
+
+} // namespace
+
+/**
+ * Like Milkdrop, a code block that can't be compiled is skipped, and the rest of the preset is still used.
+ */
+TEST_F(EquationCompileErrorTest, InvalidPerFrameCodeIsSkipped)
+{
+    // "0.99l" isn't a valid number, so this doesn't compile.
+    EXPECT_NO_THROW(context->CompilePerFrameCode("additive = above(sin(time * 200), 0.99l);"));
+    EXPECT_EQ(context->perFrameCodeHandle, nullptr);
+
+    // Executing the skipped code does nothing.
+    EXPECT_NO_THROW(context->ExecutePerFrameCode());
+}
+
+TEST_F(EquationCompileErrorTest, ValidPerFrameCodeIsCompiledAndExecuted)
+{
+    context->CompilePerFrameCode("zoom = 1.25;");
+    ASSERT_NE(context->perFrameCodeHandle, nullptr);
+
+    context->ExecutePerFrameCode();
+    EXPECT_EQ(*context->zoom, 1.25);
+}